Hydraulic crane for motor vehicles



J. E. FORSLUND Nov. 7, 1950 HYDRAULIC CRANE FOR MOTOR VEHICLES 2 Sheets-Sheet 1 Filed June 1, 1949 INVENTOR.

\\a.n E115 Foulunel ATTORNEY Nov. 7, 1950 J. E. FORSLUND HYDRAULIC CRANE FOR MOTOR VEHICLES 2 Sheets-Sheet 2 Filed June 1, 1949 Patented Nov. 7, 1 950 V UNITED STATES A T-ENT OFFICE 2,528,588 I 7 HYDRAULIC CRANE FOR MOTOR VEHICLES Johan Elis Forslund, Skelleftea, Sweden, assignor to Fabriks A. B. Forslund & 00., Skelleftea, Sweden, a corporation of Sweden Application June 1, 1949, Serial No. 96,498, In Sweden June 18, 1948 a horizontal plane. 7 1

, These objects or other advantages I obtain by constructing my improved hydraulic crane in the manner hereinafter briefly described with reference tothe accompanying drawings.

In the drawings:

Fig. 1 is a side elevation of the crane mounted on a motor lorry the front portion of which is omitted. r r V Fig. 2 is a vertical section of the means for swinging the load carrying arm of the crane in a horizontal plane.

Fig.9 is a section on line III-III in Fig. 2.

Referring to ,thedrawing, l designates the frame of a motor lorry, to which a tubular'pedestal 2 is fixed in vertical position by means of a plate 3 immediately behind the drivers cab 4. Said pedestal is provided with a collar 5 on which is turnably resting a corresponding collar 6 of a hydraulic cylinder 1 of whichanextension 8 extends through the pedestal 2. To the upper portion of the cylinder 1 there is welded a bracket 9 the form of which is so chosen as to correspond to the profile of the drivers cab and which, when itextends forwardly, the free end is located above the roof of said cab 4, as is shown. A cantilever arm I is hinged to the free end of said bracket 9 for up and down movement in a vertical plane. For the movement of the cantilever arm I0 up and down the latter is actuated by a link I I pivotally secured to said arm [0 and to the upper end of a piston l2 which is movable in the cylinder 1. A pressure fluid, such as oil or water, is in the usual manner introduced into and discharged from the lower end of the cylinder by means of a" conduit (not shown) connected toa control valve l3 mounted on the pedestal I. The valve is supplied with a pressure fluid by means of another conduit (not shown) which is connected to a pressure pump (not shown) mounted on the vehicle.

The cantilever arm I0 is preferably composed 2 Claims. (01. 212 35) of 'two plates which are secured in parallelrelationship or the arm is tubular or U-shaped in section so that there will be an inner space in which at the outer end-of the arm there is rotatably mounted a pulley -or sheave i and ad- A simijacent tothe link H anotherpulley l5. lar pulley H5 is also mounted on the cylinder 1. The purpose of these pulleys is to act as guiding and supporting means-for a hoist cable El. The

inner end of the hoist cable H is secured to a hook l8 fixed to the cantilever arm It. From the hook i8 the hoist cable ll extends downwardly to the pulley it from which it returns .upwardlyto the pulley I5 and therefrom in the space-of the cantilever arm Ill and over the pulley H. The outer and free end of the hoist cable ll carries a swivel hook [9 or similar means for attachmentto the'load to be lifted. When the cantilever arm It! is moved up or down the hook 19 will move up or down more rapidly than the end of the cantilever arm 10, with the result that the necessary movement of the cantilever arm ID in loading and unloading is reduced.

The means for turning the cylinder 1 about its axis is shown in Figs. 2 and '3. To the mounting plate 3 there is welded a horizontal plate 20 welded to the pedestal-2. A house 2| is supported by said plate 29 by means of bolts 22.

In a horizontal section the chamber within said I guiding ring 21 resting on an inner shoulder 28 of the continuation part 26 extends into the extension cylinder 8. extends through openings in the upper and lower wall of the house 2!, and to the portion thereof located within said house there is secured by means of four locking pins 29, a ring 30 having a radial projection 33 to the sides of which packings 32 are secured by means of washers 33 and bolts 34 with nuts 35. Said projection 3! forms a partition in'the arched chamber 38 formed in the house 2| around the ring 30 anditspackings 32 tighten closely against the upper, lower and arched peripheral walls of the house 2 I. Another partition 31 is bolted to the cover 23 and tightens against the ring 30 by means of packings 38 which are secured to said partition by means of washers 39 and bolts 40 with nuts 4|. At the entrance of the continuation part 26 into Said continuation part 26 I the house 2! there is arranged a packing by means of a brazen ring 42 and rings 43 of rubber.

and, similarly, a brazen ring 44 and packing rings '45 of rubber are arranged at the outer end of the continuation part 26 where the latterleaves the house 2|, and said packing rings 45 are held by means of a nut 41 threaded onto the end of V the continuation part 26. It is obvious that the connection between the extension 8 and the continuation part 26 permits no axial forces to'be transmitted from the extension 8 to the contini,

uation part 26 or inversely.

The upper wall of the house 2| is provided with 4 I 7 supported by said pedestal to turn about its axis, an extension of said cylinder extending through said pedestal, means connected with the end of said extension below said pedestal for turning apertures 48 and 49 to which conduits (not shown) are to be connected. Through said conduits a pressure fluid, such as oil or water, is introduced intoand discharged from the com partments of the chamber 36 lying on either side of the partition 3|. By altering the pressure of 4 the fluid in said compartments on both sides of the partition 3| the latter can be displaced in the chamber 36 and thus the ring 30 and the continuation part 26 are turned. As the part 25,

is connected with the extension 8 by means of the teeth 24 and 25 said extension 8 is also turned. Thus, in this manner the hydraulic cylinder 1 is turned and the cantilever arm l0 may be swung from one side to the other of the motor vehicle on which the crane is mounted.

Of course it is possible to construct the device for turning the cylinder 1 about its axis in other ways, for example, as a toothed Wheel gearing} From the foregoing, it is believed that the con-' struction, operation and advantages of the invention may be readily understood, and'I am i, aware that changes may be made in th details disclosed without departing from the spirit of the invention, as expressed, in the following claims. V f

What I claim is: I 1. A hydraulic crane for motor Vehicles, comprising a tubular pedestal, a hydraulic cylinder said extension and, thus, said cylinder, a bracket firmly secured to said cylinder, a cantilever arm for carrying a load hinged to said bracket for up and down movement in-a vertical plane, a piston in said cylinder, and a link pivotally connected with said piston and extending upwardly "from said cylinder, theupper end of said link being pivotally 'connected'to said cantilever arm.

.2. A hydraulic :crane for motor vehicles, comprising a mounting base, a tubular pedestal securedito said base, a hydraulic cylinder sup- 7 ported by said pedestal to turn about its axis,

1: Thefollowing references are of record iniithe' an extension of" said cylinder extending through chamber on both sides of said partition, a bracket firmly secured to said cylinder, a cantilever, arm for carrying .a load hinged to said bracket for up and down movement in .a vertical plane, a piston in said cylinder, and a link pivotally connected with said piston and extending upwardly from said cylinder, the-upper end of said link being pivotally connected to said cantilever arm.

JOHAN ,ELIS FORSLUND, 7

REFERENCES: CITED file' fpthis patent: V I

w U ITE *sT TEsPA EN g Date Number Name 1 420,942 Kilgore Feb. 11,1890 2,446,586 Harbaugh Aug. 10, 1948 2,462,926

Wilson et al Mar. 1, 1949 

